JPH03270751A - Rectifying part and cyclone - Google Patents

Abstract

PURPOSE:To get rid of unnecessary eddy which is unnecessary for particle separation and causes energy loss and heighten collection efficiency with whirling flow by placing a rectifying part consisting of a rectifying plate installed in the circumference of the surrounding of a conical rectifying body in the space immediately under the lower end part of an inner cylinder. CONSTITUTION:A mixed phase flow 5 of powdered particles and a fluid is supplied toward tangent line from a flowing-in cylinder 3 to a whirling cylinder 1 to generate a whirling flow 7 in the whirling cylinder 1 and the whirling flow is moved to the lower part from the upper part of the whirling cylinder 1. During the time, particles floating in the gas spring out in the wall side of the whirling cylinder 1 owing to the centrifugal force and descend spirally and are discharged out of the apparatus. The remaining fine powder, etc., with small grain size forms the whirling flow with a conveying air, etc., and is converged gradually from the wall side of the whirling cylinder to the axial part of the whirling cylinder and becomes a whirling flow with a small diameter and then moves immediate under an inner cylinder 2 and is led to the lower end part of a planer rectifying plate 11 and changes into an upward flow. A partial speed to the tangent line direction of the whirling flow is converted into a speed to only the axial direction by the rectifying part. As a result, unnecessary eddy is eliminated in the region under the inner cylinder.

Description

Detailed Description of the Invention [Industrial Field of Application] This invention relates to a cyclone that constitutes a part of a suspension plate used as a preheating device for raw materials in a cement manufacturing device, or a general powder and granular material in a pond thereof. The present invention relates to a rectifying member used in a coarse powder discharge section of a cyclone or a swirling flow classifier, and a cyclone using this rectifying member.

[Prior art] A cyclone using a rectifying member is disclosed in Japanese Patent Application Laid-Open No. 521496.
There are some as shown in 66.

That is, a multiphase flow of powder, granular material and fluid is sucked in tangentially from the upper opening of the rotating cylinder, is swirled within the rotating cylinder to separate coarse powder and fine powder, and the coarse powder is lowered inside the rotating cylinder to separate it. The air containing part of the fine particles in the pond is discharged from the lower discharge port and is taken to the center of the upper part of the rotating cylinder and passes through the inner cylinder for air discharge, which is opened in the rotating cylinder and sent to the next process. In the discharging cyclone, a rectifying vane consisting of a plurality of twisted blades having an arbitrary blade height smaller than one half of the inner diameter of the inner cylinder is placed on the same inner peripheral surface at an arbitrary position of the inner cylinder for air exhaust, as appropriate. The discharge cylinder is movably moved in the axial direction by a driving means, and the swirling flow in the inner cylinder is changed to an axial flow.

[Problem to be solved by the invention] In the area below the inner cylinder, the magnitude of the rising speed within the cyclone is thought to have a dominant influence on separation.
Most of the particles that have reached the area below the inner cylinder are the inner Mi1 for air exhaust.
1 and is presumably discharged from the system.

In other words, the region of the vortex (forced vortex) under the inner cylinder is a useless vortex that only causes a large energy loss and does not contribute to the separation effect.

In a conventional cyclone, by providing an Li flow vane at the tip of the inner cylinder, it is possible to considerably reduce pressure loss compared to a case where no rectifying vane is provided within the inner cylinder.

However, since this cyclone cannot eliminate the wasteful vortices, the pressure loss reduction is not necessarily satisfactory.
(See Figure 9 of JP-A-52-149666) In view of the above circumstances, an object of the present invention is to provide a rectifying member and a cyclone that can significantly reduce pressure loss without reducing collection efficiency. be.

[Means for Solving the Problems] The current regulating member of the present invention is provided with a current regulating plate on the conical surface surrounding the conical flow regulating member, and the cyclone of the present invention is provided with an inner cylinder above the inside of the rotating cylinder. In the cyclone, an inflow cylinder is provided tangentially on the outer periphery of the rotating cylinder, and an outlet is provided at the lower part of the rotating cylinder, and a conical fluid regulator is provided in a space directly below the inner cylinder concentrically with the inner cylinder. The purpose is to achieve the above object by disposing a flow regulating plate on the conical surface around the conical flow regulating body.

[Operation: A multiphase flow of powder and fluid is supplied tangentially from the inflow tube into the swirl tube to generate a swirl flow inside the swirl tube, and the swirl flow is directed from the top to the bottom of the swirl tube. During the movement, the particles suspended in the gas fly out toward the wall of the rotating cylinder due to centrifugal force, descend in a spiral pattern, and are discharged outside the vessel.

In addition, the remaining fine particles with small particle diameters do not form a swirling flow together with the conveying air, etc., but are gradually gathered toward the axis of the swirling tube from the wall side of the swirling tube, and become a swirling flow with a small diameter. The flow then moves directly under the inner cylinder and is guided by the lower end of the rectifying plate located there, changing from a swirling flow to an upward flow, and at this time, the tangential velocity of the swirling flow is By the action of the rectifying member, the velocity is converted to only the axial direction, and in that state it moves through the inner cylinder to the outside of the vessel. In the above process, unnecessary vortices that are unnecessary for particle separation and cause energy loss are eliminated in the region below the inner cylinder.

[Embodiment] An embodiment of the present invention will be described with reference to the accompanying drawings. An inner cylinder 2 is provided concentrically above the inside of a rotating cylinder l formed by connecting an inverted conical cylinder 1b to the lower part of a cylinder 1a, and 1
An inflow cylinder 3 is provided in the tangential direction on the outer periphery of the
A powder drop port 4 is provided at the bottom of the tube, and a multiphase flow 5 of powder and conveying air is supplied tangentially from the inflow tube 3 into the swirling tube 1, and a swirling flow 7 is created in the swirling tube 1. Because it does not cause
The swirling flow 7 is moved from the upper part of the swirling tube 1 to the lower part, and during this time, the particles p suspended in the gas are thrown out to the wall surface of the swirling tube due to centrifugal force, and fall along the inner wall surface of the swirling tube 1 to fall into the drop port 4. is discharged to the outside.

Further, in the space 8 directly below the lower end 2a of the inner cylinder 2, a flow regulating member 100 consisting of a conical flow regulating member 10 and a planar flow regulating plate 11 is provided.
is installed.

A conical flow regulating plate 10 is arranged concentrically with the rotating tube 1 in the space 8, and a plurality of, preferably 4 to 6, planar flow regulating plates 11 are provided on the outer wall surface of the conical flow regulating plate 10. .

This rectifier 10 has a third (lower surface 10a as shown in 2I)
is open and its top 10b is closed, so the airflow (conveying air) A cannot flow through the rectifier 10.The rectifier plate 11 is a triangular plate perpendicular to the axis. It is.

The outer peripheral edges lie of the plurality of planar rectifying plates 11 thus formed are located inside the virtual cylinder of the inner cylinder 2, and the powder particles are separated by the swirling flow 7 near the inner wall surface of the swirling cylinder 1. Powder and granular materials with smaller particle diameters flow into the swirling flow 7 together with the conveying air, etc.
The entire shape moves to the space S directly under the inner cylinder 2, and while its progress is blocked by the flow regulating plate 10, it is guided by the surface 11a of the planar current plate 11 disposed there, and a swirling flow is generated. It gradually changes from 7 to 12 with an upward flow, and that g! ,
The swirling flow velocity of the swirling flow 7 is eliminated and converted to a velocity only in the axial direction, and in this state, the swirling flow passes through the inner cylinder 2 and moves to the next step.

At this time, the flow inside the cyclone 15 is as shown by the chain line T in FIG. Although the wind speed Vθ which does not contribute to the separation effect remains unchanged, there is almost no wind speed Vθ in the inner cylinder which does not contribute to the separation effect.

In other words, the unnecessary vortices that cause energy loss and are unnecessary for the separation of one particle have been eliminated. In the action of the flow regulating member, the conical fluid regulating member provided in the space below the inner cylinder suppresses the rising airflow in the area below the conical fluid regulating member, reducing the fluid flowing into this area. While minimizing the driftwood resistance that is unnecessary for particle separation in the cyclone, most of the fluid flowing inside the cyclone is made to flow in the axial direction by a rectifying member in the space directly below the lower end of the inner cylinder, that is, in the space between the rectifying plates. By rectifying the flow and smoothly discharging it out of the cyclone system, the above-mentioned effect can be obtained. Note that the solid line t in FIG. 5 indicates the rectifying member 10.
The case where 0 is not provided is shown, but from the cyclone outer diameter to the center 0
As the distance x (■) increases, the wind speed Vθ increases and reaches its maximum at about 60% or 2/'3 of the diameter of the inner cylinder, after which it disappears and reaches zero at the center of the cyclone.

That is, in this case, the unnecessary vortices that are unnecessary for particle separation and generate energy loss inside the inner cylinder have not disappeared.

In addition, since the space S through which the airflow A passes gradually becomes wider from the bottom surface 10a side of the flow regulator 10 to the top lob side, the flow rate per unit area of the airflow A becomes approximately equal over the entire range of the space S. Therefore, energy loss is reduced and conveying air etc. can be constantly discharged.

Although the present invention has been described above with reference to the embodiments shown in the accompanying drawings, the present invention is not limited to the embodiments described above, and may be partially modified or modified within the scope of the gist thereof. For example, instead of closing the top 10b of the conical flow regulator and opening its bottom 10a, as shown in FIG.
is opened and its bottom surface 10a is closed to direct the airflow A to the rectifier IO.
The current plate 11 may have a twisted shape as shown in FIGS. 6A, 6B, 7A, and 7B. As shown in FIG. 8, the surface 11a is directed toward the swirling flow 7, and
The length direction is along the vertical direction, and the upper part 11b of the planar current plate 11 is fixed to the lower end 2a of the inner cylinder 2, leaving the upper part 11b of each planar current plate 11. The remaining portion 11C may be smoothly curved toward the upstream side of the swirling flow 7 to form the curved surface 11d.

Moreover, in the various illustrated flow regulating members, the conical flow regulating member may have a curved side surface instead of the straight one shown in the drawing.

Note that the straightening member 100 can be provided not only in a cyclone but also in a fine powder discharge section of a rotating type or forced vortex type wind classifier.

[Effects of the Invention] This invention is as described above, and when a rectifying member provided with a rectifying plate on the circumferential surface around the conical flow rectifier is placed in the space directly under the lower end of the inner cylinder, particles can be separated. Unnecessary energy regulation
In addition to being able to eliminate unnecessary vortices that cause loss, the current plate does not affect the swirling flow necessary for classification outside the inner cylinder, and the collection efficiency due to the swirling flow is not reduced. do not have.

In addition, since the space through which the airflow passes becomes wider from the bottom side to the top side of the one-conical fluid regulator, the flow rate per unit area is approximately equal in the entire space. Therefore, energy loss is reduced, and conveying air, etc. can be constantly discharged.

Therefore, according to the present invention, pressure loss can be reduced without reducing collection efficiency, as is clear from the following experiment using the conical rectifying member shown in FIG.

As shown in FIG.
When the lower end diameter of 0 is set as d and the ratio L/D is changed, an experiment was conducted to examine how the pressure loss ΔP and the collection efficiency η change, as shown in FIG.

In this figure, the horizontal axis is the ratio L/D(-), the left vertical axis is the pressure drop ratio A = ΔP/'ΔP1, and the right vertical axis is the collection efficiency ratio B = η/
ηl, respectively when no rectifying member is provided (ΔPI,
It is expressed as the ratio of η1.

As is clear from this figure, the collection efficiency ratio B remains unchanged at 1.0, and the longer the distance, that is, the greater the (-) value of L,/D, the more Pressure drop ratio A decreases.

Incidentally, it is preferable that the L/'D be 1.74 or more and within a range where the lower end 100b of the rectifying member does not touch the inverted cone t\J11b.

Further, the lower end diameter d of the rectifying member is set to the ratio L/D=1.0.
An experiment was conducted to see how the pressure drop ratio A and collection efficiency ratio B change when the ratio d/' D between .

In this figure, the horizontal axis shows the d/D (-), the left vertical axis shows the pressure loss ratio A, and the right vertical axis shows the collection efficiency ratio B, respectively.

As is clear from this figure, the ratio d/'D is 1.
If it exceeds 0, the collection efficiency ratio B decreases, and the above d,
/ The pressure drop ratio A decreases as D increases, that is, it is preferable that the lower end diameter d of the rectifying member 100 is equal to or slightly medium to the inner fiD.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view of the cyclone classifier of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is an enlarged sectional view of a rectifying member, and Fig. 4 is an enlarged sectional view of a rectifying member of another embodiment. A diagram corresponding to FIG. 3, FIG. 5 is a diagram showing the relationship between the tangential wind speed and the distance from the outer wall of the cyclone to the center, FIG. 6AI], and FIG. 7A is a plan view showing other flow regulating members, respectively. Figure 6B, Figure 7B
The figures are respectively front views, Figure 8 is a plan view showing another embodiment, Figure 9 is an enlarged perspective view of the rectifying member in Figure S, Figures 10 and 11 are the pressure loss ratio and collection efficiency ratio, respectively. FIG. 11...Planar current plate 11a...Face of planar current plate...Outer peripheral edge 1...Swivel tube 2...Inner tube 3...Inflow tube 4...Drop port 5... Multiphase flow 7...Swirling flow 8...Space lO...Conical rectifier

Claims (2)

[Claims] (1) A flow regulating member characterized in that a flow regulating plate is provided on a conical surface around a conical flow regulating member. (2) In a cyclone in which an inner cylinder is provided above the inside of the rotating cylinder, an inlet cylinder is provided tangentially on the outer periphery of the rotating cylinder, and an outlet is provided at the bottom of the rotating cylinder, the inner cylinder is A cyclone characterized in that a conical fluid regulator is disposed concentrically with the inner cylinder in a space immediately below, and a current plate is provided on a conical surface surrounding the conical fluid regulator.